Article dryer



April 24, 1956 H. M. ADAMS 2,742,711

ARTICLE DRYER Filed March 26, 1953 '3 Sheets-Sheet 1 INVENTOR HARRY M. ADAMS A'IT'ORNEYS H. M. ADAMS ARTICLE DRYER A ril 24, 1956 3 Sheets-Sheet 2 Filed March 26, 1953 ATTORNEYS April 24, 1956 H. M. ADAMS 2,742,711

ARTICLE DRYER Filed March 26, 1953 3 Sheets-Sheet 3 86 88 INVENTOR HARRY M ADAMS F 6. 5

Z%L BY a/M United States Patent ARTICLE DRYER Harry M. Adams, Berkley, Mich., assignor, by mesne assignments, to the United States of America as represented by the Secretary of the Navy Application March 26, 1953, Serial No. 344,694 3 Claims. (Cl. 34-147) This invention relates to a device for simultaneously drying a number of articles while handling the articles in such a way that paint thereon is not smeared.

In copending application Serial No. 324,160 by Robert L. Henry, filed December 4, 1952, a method'of mass pro ducing electronic equipment is claimed. A part of one machine that may be used in that method is disclosed herein, and said machine part accomplishes the function of driving the solvent from liquid, metalized coatings that are applied in the notches of a ceramic wafer. Due to the shape and nature of the wafers, it is essential that the wafer notch coatings be dried without smearing and without losing a definite orientation in the process of drying. Therefore, it is an object of the invention to provide a dryer that has means for conveying the wafers while they are subjected to heat, but conveying them in such a manner that the painted notches will not be contacted by another water or any part of the dryer thereby obviating any possibility of smearing the coatings in the notches of the wafers.

Another object of the invention is to provide a dryer having a fixed core with an inclined surface, preferably helical, that is shallower than the width of a wafer so that a part of each wafer overhangs the track on which the wafers move, together with a rotating wafer pusher assembly which has a number of rods that move around the core, contacting the overhanging part of each wafer and pushing the wafers from a lower entrance to the track to a higher discharge portion of the track.

A further object of the invention is to provide means at the discharge portion of the track in the core of the dryer, for guiding the wafers oi? the track while always maintaining a definite orientation of the wafers.

Other objects and features of importance will become apparent in following the description of the illustrated form of the invention.

In the drawings:

Fig. 1 is a schematic view showing the inlet path and outlet travel of wafers that are subjected to the drying treatment of the invention.

Fig. 2 is an elevational view of the dryer, portions being broken away to show internal details of construction.

Fig. 3 is a sectional view in enlarged scale showing the wafer outlet and taken on the line 3-3 of Fig. 1 and in the direction of the arrows.

Fig. 4 is a sectional view taken on the line 4-4 of Fig. 2 showing in enlarged scale, the wafer inlet.

Fig. 5 is an elevational view of the wafer moving means, parts being broken away to illustrate various details.

Fig. 6 is a plan view of a typical article handled by the dryer.

Although the dryer 10 is of general utility and may handle articles of various shapes and sizes, it has been developed especially to drive the solvent from a paint containing metal and glass particles, that has been applied by hand or by machine to the notches in a typical ceramic wafer W. As described in the referred to application for 2,742,71 l Patented Apr. 24, 1956 patent, the notches of wafers W are conveyed into a dryer, such as shown herein, and the notch coatings are dried,

leaving coatings that contain metal and glass particles, and then they are placed in magazines M which are placed on another machine that prints various contacts and circuit patterns on the wafers, and then the wafers are fired into the dryer inlet (Fig. 4) one at a time. After drying,

the wafers are discharged through an outlet (Fig. 3), pass down a chute 16 and are fed upwardly into magazine M by a magazine feed device or accumulator 18.

The specific structure involved in the illustrated embodiment of the invention is seen in Figs. 2-6, where there is a generally cylindrical casing 20 made of heat insulating material. A hood 22 is fastened by screws, on the top of casing 20 and has an open lower end in communication with the open top end of casing 20. Air vents 24 are provided in the casing near the bottom end thereof and are arranged to discharge air that is forced downwardly from the fan 26 held fixed in the hood 22 by brackets 27, the air being heated prior to entry intothe casing 20 by circulating over heater 23, also mounted in hood 22 and held in place by suitable means, as the mount ing brackets 39 that are fixed to a hood supported spider 31. Frusto conical bafile 32 and fiat baffle 34 with a downturned edge 36 direct the heated air toward the inner surface of casing 20, the baflles being secured together and to an upper collar 38 in casing 20. Suitable controls for the heater 28 and fan assembly 26 are provided to govern the operation of each.

A lower collar 42 has the casing 20 removably secured thereto for easy access to the interior structure confined in it, and the collar 42 serves the purpose of being a gear housing. Brackets 44 extending laterally of the lower collar are used for bolting the dryer 10 in place on a suitable support S (Fig. l).

A core structure 48 is mounted within the casing 24! and is stationarily secured to the lower collar 42, as by bolting to mounting brackets 59 that project inwardly of the lower collar. For fastening purposes the core structure drum or cylinder 52 is provided with a smaller diameter sleeve 54 that extends from the lower end thereof. Cylinder 52 is concentric with the casing 20 and has a helical groove cut in the outer surface thereof to accommodate a helical track 56, the latter having on its upper surface ribs 58 and 60 which form seats on which wafers W seat while theymove up the helical, inclined surface of the track. As seen in Fig. 6 the ribs are so spaced from each other and the outer surface of cylinder SZ'that a wafer W resting thereon is supported between its rnetalized notches thereby preventing paint smear as the wafer W moves on the track. Moreover, the track depth measured as the distance between the outer edge of the track 56 to the track back wall formed by the outer surface of cylinder 52, is less than the width of a wafer W, so that a portion of the wafer overhangs the track. The overhanging portion of each wafer is contacted 'by a means for moving the wafers up the inclined surface of the track, during which time the wafers are subjected to the flow of heated air.

The preferable wafer moving means comprises an upper ring 61 that includes a vertical flange 62 in which slots 64 are provided to accommodate the right angular ends of rods 66, these ends being identical to motorcycle or bicycle wheel spoke ends. There is a lower ring gear 68 in which adjustable nipples 69 are disposed in suitable apertures, the nipples receiving the opposite ends of the rods 66 thereby forming a cage-like assembly which is mounted concentrically with casing 20 and with rods 66 between the track 56 and the inner surface of the casing.

Power for the wafer moving means is taken from shaft 70 by means of gearing 72 that drives a central shaft 74, concentrically disposed with respect to the casing 20 and keyed to upper ring 61 in a boss 75 at the center of spider arms 77 that are fixed to ring 61. The shaft 74 is supported in a bearing 76 fixed in place by brackets 78 that are connected to upper collar 38, and mounted in lower bearing 80 connected by brackets 82 to the lower collar 42. The brackets 82 are passed through the central opening in ring gear 68 in order to avoid interference with the operation of the wafer moving means. Thus, upon-rotation of shaft 70, the upper part of the wafer moving means is correspondingly rotated. Through gearing 86, the lower end of the moving means is actuated at a speed identical to the speed of the means that actuates the upper end of said means, whereby there is no twist of the rods 66 in their functioning. Gearing is obvious, including gear 88 fixed to shaft 74 and enmeshed with the gear train 90, one gear of which engages the teeth of ring gear 68. For smoothness of operation, rollers 91 (Fig. 2) are provided on ring gear 68 and they contact the wall of sleeve 54.

Attention is now invited to Figs. 3 and 4 where the wafer outlet 93 and inlet 98 respectively, are shown. The outlet 93 includes an opening 92 in casing 20. A bafile 94 is adjustably secured to the cylinder 52 by means of bolts and slots in the baffle, thereby allowing the baffle to be adjusted with respect to the track 52 for operational smoothness. A curved part 96 of the baffle 94 serving as a cam extends across the track 56 and as the wafers are moved along the track, the baffle curved part 96 directs the wafer through opening 92. The wafer inlet 98 consists of an aperture 100 near the lower end of the casing 20 behind which there is a plate 101 adjustably secured to the cylinder 52. The curvature 102 of plate 101 forming a cam, directs the wafers onto curved parts of ribs 58 and 60 as wafers are fed through the casing aperture 100.

Operation The dryer is heated by energization of heater 28 and at the same time or shortly thereafter, actuation of the fan 26 takes place. When the fan is actuated, air is drawn through the hood aperture 104, blown over heater 28 and directed by the nest of baffles 32 and 34 into the space containing the wafer inclined surface between the casing Mind the cylindrcial wall 56. Finally, the heated air is discharged through air vents 24 in the lower part of casing 20.

Then the articles, as ceramic wafers W, are fed into the dryer 10, there being a variety of ways for the wafers to be fed into the inlet 98, one schematically shown in Fig. 1. Meanwhile the advancing means for the wafers are put into operation. As previously discussed, the wafers enter slot 100 between the rods 66 and come to rest upon track 56. The cam surface 102 will guide the wafers on the track 56 so that the notches of the wafer are between ribs 58 and 60 (Fig. 6). Due to the relative wafer width and track depth, each wafer overhangs the track and it is the overhanging portions that are contacted by the rods as the rods are rotated around and with respect to the core structure.

The track offers an inclined upper surface, preferably helical, for the wafers and they gradually progress to the top of the helix during which time they are exposed to the heated air that circulates in the region of the track, thus driving off the solvent that is contained in the coatings of the notches.

At the end of the wafer travel up the inclined surface, the rods pushing them slide the wafers through outlet 93 and onto a discharge chute 16.

Even though one embodiment of the invention is illustrated, modifications as fall within the scope of the following claims are sought to be protected.

What is claimed is:

1. In a dryer, a core having a helical track on which articles are adapted to slide, said core having a vertical axis, rotatable means coaxial with the core and arranged at the peripheral surface of said core for moving the articles up said helical track, said track having an article entrance near the bottom thereof, means on said track near the top thereof for directing the articles from said track, a casing encircling said article moving means and having an opening in alignment with said article entrance and a discharge opening in alignment with said article directing means, through which the articles are adapted to pass, vents in said casing adjacent the lower edge thereof, a heater mounted above said core, and means for directing air over the heater, around said track and out through the vents.

2. A hot air dryer for painted articles comprising a cylindrical casing having a closed lower end and an open upper end, said casing being positioned vertically on its lower end; a cylindrical core concentric with said casing; a helical track between the core and the casing; means to move articles along said helical track; vents in the casing adjacent the lower edge thereof; a hood positioned on the upper end of the casing, said hood having an aperture therein; heating means within said hood; and circulating means positioned in the hood for drawing air through the aperture and directing it over the heating means and downwardly between the core and the casing and out through the vents.

3. A hot air dryer for painted articles comprising a cylindrical casing having a closed lower end and an open upper end, said casing being positioned vertically on its lower end; an internal cylindrical core concentric with said casing; a helical track around the outer surface of the core; vents in said casing adjacent the lower edge thereof; a cylindrical hood positioned on the upper end of the casing, said hood having an air inlet aperture therein; drying means in said hood including a fan suspended above a heating element; and baffles positioned below the heating element, whereby upon operation of the fan, air is drawn in through the aperture, passed over the heating element, directed downwardly between the core and the casing, and discharged through the vents.

References Cited in the file of this patent UNITED STATES PATENTS 1,085,852 Duncan Feb. 3, 1914 1,472,417 Hedstrom Oct. 30, 1923 1,575,194- Dewey Mar. 2, 1926 1,836,801 Johnson Dec. 15, 1931 1,836,802 Johnson Dec. 15, 1931 2,463,570 Speicher Mar. 8, 1949 2,688,807 Ginther Sept. 14, 1954 

